Quality control of coal: The influence of sample preparation on elemental analysis results

The most common types of coal (lignite, bituminous and anthracite) are distinguished by their different chemical and physical properties. The calorific value of coal can be determined by analyzing its carbon content, for example with combustion analyzers. In addition, efficient management of the desulfurization plant requires control of the sulfur content. Compared to the large amount of coal a typical laboratory sample consists of - a 10 liter bucket or even more - the sample volume required for analysis is fairly low, only approx. 1 g. The standard DIN 51701 defines the sample amount to be tested as this relates to the particle size: The bigger the particles are, the more sample material is required.